psycopg2-binary installation fails with pg_config executable not found.

This is a bug tracker If you have a question, such has "how do you do X with Python/PostgreSQL/psycopg2" please write to the mailing list or open a question instead.

Before opening this ticket, please confirm that:

[ x ] I am running the latest version of pip, i.e. typing pip --version you get this version.
[ x ] I have read the installation documentation and the frequently asked questions
[ ] If install failed, I typed pg_config on the command line and I obtained an output instead of an error.

Please complete the following information:

OS: windows
Psycopg version: 2.9.10
Python version: 3.12
PostgreSQL version: 16
pip version: 24.3.1

In the documentation its stated that

pip install psycopg2-binary

This will install a pre-compiled binary version of the module which does not require the build or runtime prerequisites described below

But when I am trying to install this package

Collecting psycopg2-binary
  Using cached https://mirror.terma.com/pip/packages/psycopg2-binary/2.9.10/psycopg2-binary-2.9.10.tar.gz (385 kB)
  Installing build dependencies ... done
  Getting requirements to build wheel ... error
  error: subprocess-exited-with-error

  × Getting requirements to build wheel did not run successfully.
  │ exit code: 1
  ╰─> [21 lines of output]
      running egg_info
      writing psycopg2_binary.egg-info\PKG-INFO
      writing dependency_links to psycopg2_binary.egg-info\dependency_links.txt
      writing top-level names to psycopg2_binary.egg-info\top_level.txt

      Error: pg_config executable not found.

      pg_config is required to build psycopg2 from source.  Please add the directory
      containing pg_config to the $PATH or specify the full executable path with the
      option:

          python setup.py build_ext --pg-config /path/to/pg_config build ...

      or with the pg_config option in 'setup.cfg'.

      If you prefer to avoid building psycopg2 from source, please install the PyPI
      'psycopg2-binary' package instead.

      For further information please check the 'doc/src/install.rst' file (also at
      <https://www.psycopg.org/docs/install.html>).

      [end of output]

  note: This error originates from a subprocess, and is likely not a problem with pip.
error: subprocess-exited-with-error

from what is stated in the error

pg_config is required to build psycopg2 from source

but we are installing a binary package so why is pg_config needed?

psycopg / psycopg2

psycopg2-binary installation fails with pg_config executable not found. #1760